Storage and retrieval systems for medical image data such as X-ray films, CAT scans, angiograms, tomograms and MRI are commonly antiquated. For example, when image films are used in the operating room, the physician must display these photo films on a light box.
Moreover, due to the diffuse responsibilities of multiple attending physicians and treatment sites, image data for patients with complex conditions is often lost, or at best, difficult to find when needed. Hospitals maintain large "file rooms" to store bulky patient image data films. In a complex situation in which several folders are needed, a file's weight can build up to 7 kg. It has proven time consuming to obtain image data from file rooms due to administrative backlogs, to lack of specialized filing personnel and to misfiling.
Typically, the physician examines the patient in his office after the radiographical studies have been made in a hospital or diagnostic facility. These films and the information contained therein are often unavailable at the time of the examination. Thus, there is a need for remote access to these image data for rapid patient assessment and therapy recommendation.
U.S. Pat. No. 4,603,254 teaches a stimulable phosphor sheet carrying a radiation image stored therein scanned with stimulating rays. The light emitted from the stimulable phosphor sheet in proportion to the radiation energy stored therein is detected and converted into an electric signal converted to a digital signal. Digital data is created to reproduce the radiation image for use in diagnosis and storage.
U.S. Pat. No. 4,764,870 describes a system for transferring medical diagnostic information from the diagnostic site to remote stations. An internal analog video signal from imaging diagnostic equipment such as a CAT scanner or MRI equipment, is converted to an analog video signal of different, preferably standard, format that is stored and transmitted in the reformatted image information to the remote terminal. The received signal is stored, decoded and applied in appropriate analog video form to an associated CRT display for reproduction of the diagnostic images.
U.S. Pat. No. 5,005,126 shows a system for transferring medical diagnostic information from the diagnostic site to remote stations similar to that found in U.S. Pat. No. 4,764,870.
U.S. Pat. No. 5,019,975 teaches a method for constructing a data base in a medical image filing system comprising the steps or recording information indicating the time at which each medical image is recorded and a rank of importance for each medical image as image retrieval signal data for image signals corresponding to each medical image; recording the number of times the image signals corresponding to each medical image have been retrieved as image retrieval signal data and incrementing the number each time the image signals are retrieved; and when the data base is full of image retrieval signal data, deleting the image retrieval signal data corresponding to the image signals of the medical image in which at least (1) the time at which the medical image was recorded earlier than a predetermined time and (2) the rank of importance of the medical image is lower than a predetermined value.
U.S. Pat. No. 4,611,247 describes a radiation image reproducing apparatus to read a radiation image from a first recording medium as a visible image. Input devices of the apparatus enter data which are associated with a method of exposing an object to a radiation and object's exposed part. In response to the input data, a processing condition determining unit determines conditions optimum for a gradation processing and a spatial frequency processing. A processor system is provided for reading the radiation image stored in the first recording medium and processing the radiation image on the basis of conditions which the processing condition determining unit determines in response to the input data associated with the radiation image.
U.S. Pat. No. 4,750,137 discloses a method and a computer program for performing the method for optimizing signals being exchanged between a host unit and an addressable-buffer peripheral device. The program optimizes an outgoing signal from the host unit by (1) creating an updated-state map representing the state of the peripheral device buffer expected to exist after processing by the peripheral device of the outgoing signal, (2) performing an exclusive-or (XOR) operation using the updated-state map and a present-state map representing the existing state of the buffer, and (3) constructing and transmitting a substitute outgoing signal which represents only changes to the buffer, and in which all premodified field flags are turned off. Position-dependent characters, such as attribute bytes, are translated into nondata characters prior to incorporation into a map, and are retranslated into their original form for use in the substitute signal.
U.S. Pat. No. 4,858,129 teaches an X-ray CT apparatus in which a plurality of dynamic tomographic images obtained by repeatedly photographing a region of interest of a subject under examination are stored in an image memory for subsequent display on a display device. A processing device extracts data of pixels along a certain line common to all of the tomographic images and stores the pixel data in the image memory, in the order of photographing time of the tomographic images, thus forming a time sequence image formed of picked-up pixels. The processing device reduces a tomographic image and the time sequence image and rearranges the reduced images in one frame area of the image memory for simultaneous display thereof on the display device.
U.S. Pat. No. 5,021,770 discloses an image display system having a plurality of CRT display screens. The system is of the type in which a number of images of specific portions of a patient having a specific identification code are selected from among a multitude of X-ray image taken by a plurality of shooting methods, and when the regions or interest are specific, a plurality of appropriate images are further selected using the previously stored amplitude values for the regions and shooting methods and displayed on the plurality of CRT display screens. In order that the segments to be inspected can be pointed to on the screen on which the image of the patient is displayed, a memory is provided which is adapted to previously store codes corresponding to the specific image of the patient and to specify the respective regions of the image in such a manner that they correspond to the pixel positions of the image.
U.S. Pat. No. 4,879,665 teaches a medical picture filing system composed of a picture data memory device, a picture data input-output device for inputting/outputting the picture data, a retrieving device for storing the picture data into the memory device and extracting it therefrom on the basis of retrieving data, a retrieving data input device for inputting the retrieving data into the retrieving device, a retrieving data storing device for storing the retrieving data, the retrieving data being classified by block of information obtained in one-time examination. When medical pictures are filed, retrieving data collected for each examination is utilized for reducing the amount of retrieving data, while when reproduced, retrieval is carried out for each one-time examination thereby shortening the time required for retrieval.
In light of recent advances in computer data basing, digitization and compression of image data, image enhancement algorithms and cost effective computer technology, the means for improved storage and retrieval of vital patient image data is now possible.
Such system should include the following major features:
1) means to more compactly store and more efficiently retrieve image data and automatically identify the data by patient name, image type, date and the like; PA1 2) means for physicians to quickly and remotely access particular patient image data at the medical facility even if archived at several different locations; PA1 3) means to prevent loss of vital image data due to ordinary human handling and misplacement errors; PA1 4) means to quickly and affordably access image data from the physician's office; PA1 5) means to enhance the medical images by both contrast enhancement and zooming for improved diagnostics and/or surgical guidance; and PA1 6) means to quickly and conveniently access image data and display on a large screen in the operating room with any desired enhancement or expansion.
As described more fully hereinafter, the present invention provides means to accomplish these goals. The system uses both general purpose system elements well known to those practiced in electronic arts and specific elements having significant novelty.